LOUISE MENSCH has sensationally resigned from her duties as MP in a bid to spend more time with her family.

THE MP who admitted it was “highly probable” that she once took Class A drugs has sensationally quit.

Chick-lit author Louise Mensch announced yesterday that she was moving to New York with her three children to be with her second husband Peter, manager of rock megastars Metallica.

In her resignation letter to Prime Minister David Cameron, the MP for Corby said she had been “struggling for some time to find the best outcome for my family life”.

She added: “And I have decided, in order to keep us together, to move to New York.

“With the greatest regret, I am thus resigning as a Member of Parliament.”

The move comes months after Mensch attacked the PM for failing to promote her – despite only being elected in 2010.

Cameron now faces the prospect of a triple by-election defeat on November 15.

Cardiff South and Manchester Central are also up for grabs. Both are likely to stay Labour after Alun Michael and Tony Lloyd stand down in a bid to become police commissioners.

Corby came into Tory hands in 2010 after being Labour for 13 years and the Conservatives have a knife-edge majority of only 1951.

Mensch’s decision led to speculation that Boris Johnson could use the opportunity as a springboard to become Tory leader – but the London mayor ruled out standing for the seat, saying: “I’m sure Corby is a lovely town but I have a fantastic job running the best big city on the planet.”

Mensch, 41, who revealed that Cameron had allowed her not to attend Parliament on Thursdays so she could be with her young family, later said on Twitter: “I am devastated by the necessary decision that I have had to announce.”

Cameron said Mensch had been an “inspiring” MP and hinted that she had been in line for a role in the Government.

He accepted her resignation with “enormous regret”, saying: “It goes without saying that I had wished to see you serve for longer and at a more senior level.”

It was in January that Mensch complained she was always ignored for promotion, saying: “It’s kind of annoying. What do I have to do to get promoted over here?’”

Last month, she shocked viewers of BBC’s Question Time when she admitted that doing drugs in her youth had “messed with her head”.